The guys from Tru Biofuels were out in Venice at the Abbot Kinney street festival (which was pretty green) with a Mercedes Benz UNIMOG, a German military vehicle that was about that size, but with four doors not six.

They run it on waste vegetable oil.

Still... it's a lot of used veggie oil. And there's still emissions coming out of the tail pipe. People get all excited about biofuels, but I think that the future for most passenger vehicles is combustion-less. And powered by Photovoltaics.